In 1828 he was awarded the prize offered by the Societe d'Encouragement pour l'Industrie Nationale for a process of making artificial ultramarine with all the properties of the substance prepared from lapis lazuli; and six years later he resigned his official position in order to devote himself to the commercial production of that material, a factory for which he established at Fleurieux sur Saone.
Chaptal for a cheap colouring matter, as bright as ultramarine and capable of standing the heat of the porcelain furnace.
This species from the high north of Europe and Asia carries green eggs, and above them a bright pattern in ultramarine (Sars, 1896, 1897).
In 1814 Tassaert observed the spontaneous formation of a blue compound, very similar to ultramarine, if not identical with it, in a soda-furnace at St Gobain, which caused the Societe pour l'Encouragement d'Industrie to offer, in 1824, a prize for the artificial production of the precious colour.
Processes were devised by Guimet (1826) and by Christian Gmelin (1828), then professor of chemistry in Tubingen; but while Guimet kept his process a secret Gmelin published his, and thus became the originator of the "artificial ultramarine" industry.